diff --git a/source/const.inc b/source/const.inc
index 2aa1dcad..7e1287a5 100644
--- a/source/const.inc
+++ b/source/const.inc
@@ -359,4 +359,4 @@ const
   HELPERNODE_PROFILE = 4;
 
   // A set of characters which need not to be quoted
-  IDENTCHARS = ['A'..'z', '0'..'9'];
+  IDENTCHARS = ['A'..'Z', 'a'..'z', '0'..'9'];